I would check with s&w service dept about the mag not fitting in your gun when fully loaded my wifes 40c works just fine , maybe you have the wrong mags.
As for carrying a gun with one in the pipe. It is a must for ccw.and you know that.
You have spent the $ for a great gun but it dose not stop there, you must invest time to handle this weapon with confidence.
THIS IS NOT A GAME, IT IS SELF PROTECTION, POSSIBLE LIFE OR DEATH.
Find a good holster that protects the trigger and train, train , train
Hitting a target is at the range is 20% of ccw, figure out the other 80% it does not come overnight
Good luck and be careful